Reversing valve mechanism



Jan. 2, 1940. .1. E. WHITFIELD REVERSING VALVE MECHANISM Filed Dec. 9, 1938 '4 Sheets-Sheet 1 i IEVIENT OR.

ATTORNEY.

Jail 1940- 1.1. E. WHITFIELD 2,185,614

REVERSING VALVE MECHANISM Filed Dec. 9, 1938 4 Sheets-Sheet 2 WIMP u" I f.

ATTORNEY.

2, 0- J. E. WHITFIELD ,185,6 4

REVERSING VALVE MECHANISM Filed Dec. 9, 1958 4 Sheets-Sheet s ATTORNEY.

Jam 1940- J. E. WHITFIELD ,185,614 I REVERSING VALVE MECHANISM Filed Dec. 9, 1938 4 Sheets-Sheet 4 l A A. V I

"j? i I 74 i I 1 z9 76 I I 80* l I I I I I v W77 1N ENTOR. I g W 2 BY A" ATTORNEY.

' .vehtion is shown wherein:

Patented Jan. 2,1940

UNITED STATES PATENT OFFICE REVERSING VALVE MECHANISM Joseph E. Whitfield, Grove City, Pa.

Application December 9, 1938, Serial No. 244,801 13 Claims. (01. 137 -111) This invention relates generally to reversing valve mechanisms for the control of the flow of fluids and more particularly" to the control of the flow of air or gas.

The principal object of this invention is the provision of a new and improved type of reversing valve characterized by the use of a flexible valve member wherein by the shifting of the valve helical passageways are provided for the selective connection of a plurality of ports or conduits.

Another object is theprovision of an improved means for the operation of the valve.-

Another object is the provision of an improved manifold to be used in connection with the valve.

Another object is the arrangement with anini; ternal combustion engine of a reversing valve for controlling the scavenging of the engine.

Other objects will appear from the following description and claims.

In the accompanying drawings a practical embodiment illustrating the principles of this in-' Fig. l'is an end elevation of an internal combustion engine and a scavenging air blower and reversing valve connected thereto.

Fig. 2 is a sectional view taken on the line 2-2 of Fig; 1 showing the driving connection of the reversing valve.

Fig. 3 is a perspective view of one form of the reversing valve.

Fig. .4 is a plan view of the reversing valve with the valve member in the reversed position of that shown in Fig. 3.

Fig. 5 is a plan view of one blade of the valve shown in Fig. 3. I

Fig. 6 is a perspective View of the manifold employed between the reversing valve and the blower shown. in Fig. 1. i 1

Fig. '7 is a vertical section taken through the valve, the manifold and the blower illustrating the inter-connecting passageways therebetween.

- of Fig. 1 illustrating one type of servo-motor to operating the reversing valve.

Fig. 9 is'a side elevation of the servo-motor I shown in Figs. 1 and 8.

versible type of internal combustion engine designed to employ air for scavenging each cylinder after combustion. The scavenging air is furnished by the rotary air blower ll driven from the crank shaft I2 of the engine In as through the chain or belt drive l3. The air is drawn through the cleaner l4 and passes down the intake duct l5 to one side of the dual port reversing valve l6 whence it is guided to the proper side of the manifold l! which directs it to the blower H from whence it passes back up through the other side of the manifold I1 and the reversing valve Hi, the duct iii to the scavenging air manifold I9 in the engine l0. By means of the ordinary valvular arrangement in the engine ID the scavenging air is passed through each cylinder after combustion has taken place and is exhausted carrying the residue of the products of combustion with it, leaving the cylinderwith a clean air charge for the next combustion. The simplest and most economical type of blower for this purpose was found to be one that operates in either direction withthe same characteristics and may be directly driven by the internal combustion engine, thus eliminating the use of mechanical reversing mechanism between the engine and the blower. With this arrangement an air reversing valve findgoperating mech-.

anism is required which provides "i -"'simpliiled 1 structure of relatively few parts, thus diminishing the chances of failure under continued operation.

The valve It comprises a hollow casing 20 having two openings or ports 2| and 22 at the tance across the casing and are disposed inhorizontal planes with one set of ports positioned at .ninety degrees to the other set of ports as, illustrated in Figs. 3 and 4. Intermediate of the top and bottom ports the valve casing is provided with 'a'bore having a circular path 21 between 40 the ends of the transverse bars 23 and 26, where it is tangent to the inner flat wall 28. Ii this circular path were drawn on a flat surface it would simulate the shape of a sine curve consisting of The surface of, this path may be straight lines. considered as the valve seat inthe sense that it represents the stationary portion of the valve body which coacts with the movable portion of the valve in performing the valvular function.

Interposed between the two sets of ports and cooperating with the valve seat 21 is a valve member consisting of a flexible wall having one end.

stationary and in coincidence with one of the transverse bars, such as the lower bar 26, while the other end of the wall is rotatable through into either of two positions in registration with the other transverse bar,'such as the bar 23. Thus by swinging the movable end of the flexible wall, producing helical passageways on both sides thereof, the ports in the top of the casing are connected to the ports in the bottom of the casing which are disposed 90 from each other and by reversing the wall through 180* this connection may be reversed, viz., port 2| may be connected to port while port 22 is connected to port 24, or port 2| may be connected to port 24' while port 22 is connectedto port 25,.

In many installations the valve wall may be formed of a sheet of flexible material, such for instance as rubber or a textile, or any other suitable flexible material, but for such uses as that for which the illustrated embodiment is intended it is preferable to employ the structure shown in the drawings.

Thus valve 36 is made up of a series of superimposed blades 3| substantially equal in length to the diameter of the circular bore forming the path 21. Each blade is rectangular in cross section and is substantially equal in size to that of the transverse bars 23 and 26. The ends of the blades are arcuately shaped so that they will mate with the circular path 21 with agiven clearance.

Each of the blades, 3| are rotatably supported on the vertical shaft 32 journaled in the transverse bars 23 and 26 and which extends up through the top bar 26 .into the space between the air duct's 5 and I8 as illustrated in Fig. 2. The upper and lower surfaces of the central portion of the blades 3| are recessed as indicated at 33 for receiving one-half of the key members 34. Each key is provided with a bore for rotatably mounting them on the shaft 32. The end or nose 35 of each key is provided with vertical side faces 36 which mate with complementary faces 31 on the sides of the recesses 33, producing full contact area therebetween. It will be noted that the faces 31 of each recess are substantially parallel and are spaced further than the width of the nose 35 of the key. With a valve having seven blades as shown, this space should be such that the nose of the key moves through an arc of 11 A between the faces 31.

The lowermost blade 3| may be similarly keyed to thetransverse bar 26 or it may be held between the limits of its movement by means of the bolts 38 shown in Fig. 4 which extend through the casing 20 on each side of the end of the blade which permits the blade to move 11%; on either side of the transverse bar 26.

The recess inthe top surface of the uppermost blade 3| is engaged by the driving key 39 which is one-half as thick as the other keys and istherefor flush with the top'of the blade. This key has a depending collar 46 which snugly flts the shaft 32 and is flxedly attached thereto. By rotating the shaft so that the uppermost blade lags approximately 11 4 from complete alignment with the transverse bar 23 each successive blade also lags in a position of 11%. The center of the lowermost blade is then 11 A from the center of the bar 26. the next blade 22 /2. and so on to the uppermost blade which is '18% or Il from alignment with the top bar 23. These blades simulate two circular stairs connecting the upper port 2| with the lower port 24 and the upper port 22 with the lower port 25 and form a helically shaped wall between these passageways as shown in Fig. 3. By rotating the shaft 32 in the opposite direction the uppermost blade may be turned through 157 .or until it is within 11%) from the transverse bar 23. The upper blade carries each successive blade through their respective arcs reversing the helical. wall and thereby reversing the port connection completing the passageways between the ports 2| and 25 and between the ports 22 and 24 as shownin Fig. 4.

The shaft 32 may be operated by any suitable electrical, mechanical, or pneumatic servo-motor which is energized when the reversal of the internal combustion engine is initiated or in sequence of the actual reversal thereof. The servo motor may be directly connected to theshaft 32 between'the air ducts l5 and I8 or beveled gears 4| and 42 may be employed as shown in Figs. .1 and 2 for connecting the shaft 32- to the horizontal shaft 43. The servo-motor 44 illustrated on the drawings is connected to the shaft 43 and is pneumatically operated. This motor comprises the casing 45 closed at one end and provided extending through the wall of the casing. The

pneumatic motor rotor 50 comprises 'a simple vane having a circular hub 5| bored to receive the shaft 43 and is secured thereto by the key 52. The outer end of the vane is arcuately shaped to fit the cylindrical wall of the chamber 46 and the abutment 48 is provided with the cylindrical surface 53 for mating with the hub 5|. A packing 54 is provided in the center of the surface 53 for sealing the hub of the rotor.

Each side of the .casing 45 is provided with the air ports 55 and 56 which are connected to mating passageways 51 and 58 in the valve body 53 bolted to the sides of-the motor casing and which are controlled by the valves 66. The valves 66 comprise a cylindrical head 6| with an integral stem 62 disposed normal thereto and having a passageway 63 through the head and the stem which connects the air inlet 64 to the passageway 58.

These valves are operated by the air'which actuates the rotor 50 and is controlled by a suitable reversing master valve connected to-a source of air supply. The master valve isin turn operated by the reversing mechanism of the internal combustion engine. As shown at the right in Fig. 8 the air is being admitted to the inlet 64. The air pressure acts against the head passageways 51 and 58,.thus requiring all of the I air supplied to pass through the central bore 63 of; the stem, to the port 58 to the chamber 46 back of the pneumatic rotor 50, causing it to swing in a counterclockwise direction to the other 1 side, thereby rotating theshaft 43 and actuating 1 the valve 80. q I

The air in the chamber on the leading side of the rotor 50 is driven out the port 56 and, impinges against the head 6| of the valve 66, 6 moving it to the left or away ,from the motor,.

thus permitting the air to exhaust out the ports 65. The movement of the valve outwardly opens up the port connectingthe passageway iii areas. 3

Assuming that the internal combustion en- 88 with the passageway 51. when the rotor 58 approaches the limit of its movement the arcuate end closes the port 55 and all of the air in front of the leading side of the vane must be exhausted through the port 58, the passageway 58, the port 88, the passageway 51 and is exhausted out the ports 85. The port 68 is purposely restricted to limit this discharge at the end of the stroke of the rotor 58 to produce a cushioning effect and prevent it from striking the abutment 48.

When the opposite side of the motor 44 is energized to reverse the valve 38 the motor valves 88 function in the same manner and the rotor 50 is moved in a clockwise direction.

The head 41 which encloses the pneumatic chamber 48 in the casing 45 as shown in Fig. 9 is provided with a transversely disposed rib, 88, the one side 89 of which'is substantially coincident with the axis of the shaft 43. A spring 'loaded bumper stop I8 is carried by saidrib adjacent each end thereof with its contacting portion extending beyond the side 89 and arranged to engage the bumper lug II which projects inwardly from the crank arm 12 secured to the shaft 43. The very tip of the shaft 43 is squared, as indicated at I3, for receiving a hand crank for manually operating the valve 88.

The end of the crank arm I2 is bifurcated for receiving the end of the tubular sleeve I4 which is pivotally secured thereto by the pin 15 driven through aligned holes in these parts. The tubular sleeve I4 is arranged to telescope over the rod I8 which is pivoted at 11 on the bracket 18. This bracket extends outwardly from the base plate I8 secured to the duct frame and is arranged to support the servo-motor 44'.

The tubular sleeve I4 and the rod I8 are provided with oppositely disposed seats for holding the helical spring 88 which encircles these members and which forms ,a spring loaded toggle functioning to retard the movement of the servomotor rotor 58 until it passes dead center, then aiding its movement through the rest of the stroke.

The bumper I8 and the toggle spring 88 hold the rotor 58 in the position indicated in dotted lines inFig. 8, thus providing a small space between the rotor and the abutment 48; to pre-' vent rapid expansion of a large volume of high pressure air. The compressed air moves the rotor 58 and compresses the spring 88 until it passes dead center or the mid position of the stroke, after which time the spring pressure aids the movement of the rotor 58. If the compressed air is allowed to continue to flow to the motor after the rotor reaches its normal stop position, which is indicated by dotted lines in Fig. 8, the continued pressure forces the blade slightly past the normal stop position compressing the spring loaded bumper, allowingthe compressed air to escape through the exhaust ports 85. when the air ceases to flow to the motor the spring of the bumper returns the blade to its normal positionj as indicated by dotted lines, and it-is held there by the toggle spring 88. The speed of the movement of the pneumatic rotor 58 is determined by the size of the passageway 88 and the operator may turn on any amount of air pressure to the motor but its movement is restricted to the amount admitted by this pasgine I8 is rotating in a counterclockwise direction the air blower II is being turned in the same direction and the. air travels into the cleaner I4 down through the duct I into the port 2I of the valve I8 and out the port 24 'into' the chamber 82 of the manifold II where it separates and passageway 9i in the manifold to the chamber 92. The air being drawn down-through the passageway 84 travels through the port 93 past the upper rotary abutment 98 and is carried bythe rotor 88 of the blower to the port 94 adjacent the lower abutment from whence it is forced up the passageway 95 to the chamber 92 in the manifold ll.

The air is then forced from the chamber 92 through the lower port of the valve I6 and out the upper port 22 through the duct I8 to the engine.

Upon reversing the internal combustion engine so that it rotates in a clockwise direction the blower II is also reversed and the servo-motor 44 must then be energized to reverse the valve I8 to the position indicated in Fig. 4. The air is then drawn through the cleaner I4, the duct I5, the upper port 2| of the valve l8 and through the lower port 25 to the chamber 92 in the manifold II where it is separated, part of the air traveling down through the passageway 95, the port 94, where it is picked up by the rotor 88 and forced through the port 88, the passageway 84, to the chamber 82 of the manifold I I. The other part of the air travels from the chamber 92, through the passageway 9|, the port 89, where it is picked up by. the blower rotor 88 and forced out the port 86, through the passageways 85' and 83 to the chamber 82 of the manifold II.

The air then passes through the lower port 24 of the valve l8 to the upper port 22 and through the duct I8 to the engine l0. Thus by the use of the reversing valve IS the air is directed to the.

combustion engine regardless of the direction of rotation of the blower I I and a simple direct drive between the engine and the blower may be employed.

Referring now to Fig. 10, 96 represents the cam shaft of the internal combustion engine. This cam shaft is provided with two sets of cams for each valve of the ngine, with their contours arranged 180 from each other, and by shifting the cam shaft axially between given limits one set of cams may be selectively positioned to operatively engage their respective valves, causing the engine to rotate in a given direction, and when the cam shaft is moved to the other limit the other set of cams cause the engine to rotate in the reverse direction. To simplify the structure a manually operated lever 91 pivotally supported on the engine is shown for, shifting the cam shaft, but it is obvious that this lever may be connected to any suitable motor which when energized will swing it to either position for revers- The lever 91 is pivotally coning the engine. V n'ected through the link 98 to the pneumatic master reversing valve 99 which when shifted by the lever selectively connects the source of air pressure I88 with the corresponding side of the se'rvo-motor 44, thereby effecting a reversal of the valve 30.

The pressure gauge connected to the supply line I indicates when the reversing operation 5 is complete by showing a sudden drop in the line pressure, which is caused by the discharge of the air to atmosphere out the exhaust openings 65 when the rotor vane 50 in the servo-motor 44 has reached its ultimate reversed position. Nil represents a time release valve which is opened by a partial movement in either direction of the reversing lever 91 to admit air to the master valve 99 and which is responsive to a sudden drop of pressure to cut off the supply of air to the master valve and the servo-motor and thus avoid unnecessary waste of compressed air when the reversing operation has been completed. The complete movement of the reversing lever 91 is prevented by the time release valve until the air pressure has dropped, indicating a completion of the reversal of the valve 30. Thus failure of the reversing operation of the valve 30 prevents the engine from reversing.

This apparatus may be advantageously employed for marine service wherein the engine III is ordinarily of the Diesel type. It is necessary to completely stop the engine in order to effect a reversal; However this may be accomplished as quickly as that required by mechanical gear reversing mechanism or other similar types which are considerably more expensive and are subject to wear, requiring expensive replacement.

I claim: 1. In a reversing valve, the combination of a casing having a plurality of ports at each end thereof, a flexible valve wall mounted in the casing intermediate of the ends thereof, and means for shifting the wall to provide passages selectively connecting individual ports at one end of the casing with individual ports at the other end of the casing.

2. In a reversing valve, the combination of a casing having a plurality of ports at each end thereof, an annular seat in the casing, a flexible 4:, valve wall member cooperating with the seat and having one end stationary, and means for shifting the valve wallto provide a passage selectively connecting individual ports at one end of the casing with individual ports at the other end of the casing.

3 In a reversing valve, the combination of a casing having a plurality of ports, an annular valve seat in the casing, a flexible valve wall comprising a plurality of blades rotatably mount- 55 ed in axial alignment and having their free ends coacting with the valve seat, and means for moving the blades into helical arrangement to form passages selectively connecting the ports.

4. In a reversing valve the combination of a casing having ports in the opposite end thereof, a

flexible valve wall mounted in the casing, and means for shifting said wall 'to provide helical passages selectively connecting said ports.

5. In a reversing valve, the combination of a on casing having an equal number of ports in the opposite ends thereof, a flexible valve wall mounted in the casing, and means for shifting said wall to, provide an equal number of helical passages selectively connecting said ports.

6. In a reversing valve, the combination of a casing having ports in its opposite ends and a valve seat intermediate said ports, a flexible valve wall arranged to coact with the seat, and means forv shifting the valve wall to form helical passages selectively connecting pairs of opposed ports.

7. In a reversing valve, the combination of a casing having ports in its opposite ends and a circular valve seat intermediate said ports, a flexible valve wall comprising a plurality of blades rotatably mounted in axial alignment, and means for moving said blades into helical arrangement to form a helical wall defining passages selectively connecting opposed ports.

8. In a reversing valve, the combination of a casing having ports in its opposite ends and a circular valve seat intermediate of the ports, a flexible valve wall comprising a plurality of blades rotatably mounted in axial alignment and having their free ends coacting with the valve seat, and means for moving said blades into helical arrangement to form passages selectively connecting opposed ports.

9. In a reversing valve, the combination of a casing having ports in its opposite ends and a circular valve seat intermediate of the ports, a flexible valve" wall comprising a plurality of blades rotatably mounted in axial alignment and .having their free ends coacting with the valve seat, and lost-motion connection between adjacent blades for moving said blades into helical arrangement to form passages selectively connecting opposed ports.

10. In a reversing valve, the combination of a casing having a pair of ports in each end thereof, and a valve member mounted in said casing comprising a flexible wall having one end stationary and coincident with the partition between one pair of ports and having its other end movable to flex the wall into either of two positions to selectively connect the individual ports at one end of the casing with either port at the other end of the casing.

11. In a reversing valve, the combination of a casing having a pair of ports in each end thereof,

an annular seat in said casing, and a valve member mounted in said casing comprising a flexible wall cooperating with said seat and having one end stationary and coincident with the partition between one pair of ports, and having its other end movable to flex the wall into either of two positions to selectively connect the individual ports at one lend of the casing with either port at the other end of the casing.

12. The combination with a reversing valve and a shaft arranged to'operate the same, of opposed resilient stops to limit the movements of the valve, and resilient means cooperating with the stops for maintaining the valve in an assumed position.

13. The combination with a reversing valve and a shaft arranged to operate the same, of a crank mounted on the shaft, resilient means for limiting the movement of the valve, and a spring toggle mechanism connected with the crank and cooperating with the resilient means for holding the valve in an assumed position and against accidental movement.

JOSEPH E. WHITFIELD. 

